Exploration of Mesh-Based FPGA Architecture: Comparison of 2D and 3D Technologies in Terms of Power, Area and Performance

In this paper, we propose a 2D and 3D interconnect network based on a Mesh-of-Clusters (MoC) topology for the implementation of an efficient Field Programmable Gate Arrays (FPGA) architecture. Proposed MoC-based FPGA architecture presents a new hierarchical Switch Box (SBs) and depopulated intra-cluster interconnect based on the Butterfly-Fat-Tree (BFT) topology. Long routing wires which span multiple SBs in every row and column were used in order to improve performance. By adjusting the percentage of long wire and span, we can design and build 3D high density MoC-based FPGA. To design 3D MoC-based FPGAs, we cut the 2D FPGA into two equal FPGA dies and we adjust the long wire span factor to connect the two dies. Then, these long wire segments are converted as 3D through silicon via (TSV). We present also a design methodology and CAD tools to explore the performance of proposed 2D and 3D MoC-based FPGA architectures in term of power, energy, area and delay. Experimental results with large benchmarks show that with 3D MoC-based FPGA the average gains in terms frequency, energy and area are 23%, 37% and 47% respectively, compared to 2D MoC-based FPGA.